Soy food increases fertility rates

This study examined the effect of soy food intake in women having fertility treatment.

Infertility, or the inability to conceive, affects 5-15% of couples worldwide. Assisted reproductive technology (ART) refers to any treatment in which the female egg, the male sperm, or both are handled, and pregnancy is achieved in an artificial manner.

Previous research has shown that women taking large doses of soy food supplements have higher pregnancy rates. However, it is not known whether the same effects can be achieved through normal dietary intake of soy. 

A total of 315 women took part in this study. They were all due to start a course of ART fertility treatment. Before they started ART, the women completed a food questionnaire. They were asked how much soy-containing food they had eaten over the past 3 months. 211 women had eaten various forms of soy food (ranging from low to high intake), while 104 women had not eaten any soy-containing food.

The study found that after ART, the fertilization rate was 6% higher in women who had consumed soy foods in the 3 months before treatment, compared to those who did not. In addition, clinical pregnancy rates were 11% higher and live birth rates were 13% higher in soy food eaters compared to non-eaters. 

Statistical analysis revealed that compared to women who had no soy, those who took in 0.54 – 2.63 mg/day had a 32% increased chance of a live birth, those who took in 2.64 – 7.55 mg/day had an 87% increased chance and those who took in 7.56 – 27.89 mg/day had a 77% increased chance of a live birth. 

This study concludes that eating soy foods in the 3 months before starting fertility treatment may increase treatment success rates. 

The authors relied on the patients to think back in time and remember how much soy food they had eaten in the previous 3 months. Therefore, the levels of soy intake may not be fully accurate. 

Talk to your doctor if you are thinking of introducing soy products in to your diet.